Diacetyl rest without taking gravity

Most of the schedules out there do it based on percentages or points above FG. Well I’d rather not take regular hyrdometer readings just to pinpoint that due to increased infection risk. It seems best practice is to ramp it up to the low 60’s when it’s nearing the end of fermentation. Anyway to guess that or should I just do it around day 7?

A little bit of history. Beer is a Vienna Lager, OG 1.053. I pitched a big starter of WLP820 after aerating with pure oxygen and diffusion stone for about 90 seconds. Keeping at a constant 51*F. I had a about an inch to inch and half krausen after 24 hours (which I understand is very quick for this strain).

After fermentation has been going for about 5 days, smell and taste your beer. If it doesn’t have any diacetyl, then you can safely skip the D rest. If it does, then wait until it seems like the krausen is just beginning to settle down a little bit, then bring it up. I imagine this should happen on about day 6 or 7, something like that, but might be even earlier? There’s no real rule as to the number of days for a lager primary fermentation – might be 4-5 days, might be 3 weeks. Bottom line though is that you don’t need a D rest unless you taste diacetyl! Still, it wouldn’t hurt anything either if you did one just for the heck of it. Just optional.

I personally like to do them on most beers, especially lagers. You can try this as well, as diacetyl won’t always be evident from a straight taste from the fermenter.


My SOP for lagers is:

Pitch at 48-50F and hold for 7 days.
At day 7 slowly start raising the temp 1-2 degrees per day.
After about 7-14 days the temp should be up around 64F.
Hold at 64F for a day or two then drop to largering temp or rack to secondary and drop.
I don’t drop slowly. I just crank it down to 35F and let it go. Have never had an issue.

As you can see it’s not overly precise or complicated, but it works for me. My numbers are not set in stone since I usually raise it 1 degree per day, but often miss a day here and there. If I do, I just raise it 2 degrees the next day.

I don’t take readings at all until I’m done the d-rest and even then, sometimes don’t. Sometimes I won’t take a reading until I keg it weeks/months later. `